Project Summary and Abstract Colorectal cancer (CRC) screening saves lives but CRC screening rates remain low among Chinese Americans, the most populous Asian American group. Little is known about how to conduct effective and culturally appropriate community-based health promotion in this ethnic group. Lay Health Worker Outreach (LHWO) is an effective modality to promote some healthy behaviors in some communities, but much remains unknown about this approach and no prior work has been done with Chinese Americans. This proposed project seeks to expand understanding of what constitutes a lay health worker (LHW), how those characteristics determine the effectiveness of LHWs as health educators on CRC screening, and the relationship of those characteristics to a particular community and culture. Using quantitative and qualitative methods and a community-based participatory research (CBPR) approach, the project will develop and implement a group randomized controlled trial to evaluate LHW effectiveness in promoting CRC screening among Chinese Americans age 50 and older with a pilot component to evaluate the role of Traditional Chinese Medicine (TCM) healers as health educators. We will refine and implement a culturally and linguistically appropriate community outreach program based on LHWs to promote CRC screening among Chinese Americans age 50 to 75. The developmental work will be based on a prior successful pilot project, focus groups, and key informant inputs. These materials will be used in the first aim, which is to evaluate the effectiveness of LHWO on receipt of CRC screening among Chinese Americans in a group randomized trial using LHWs to deliver CRC education (intervention) compared to a CRC brochure (comparison) in a sample of Chinese Americans age 50 to 75, living in San Francisco, and recruited through social networks of LHWs. Twenty-six LHWs each will be assigned to the intervention arm and 26 to the comparison arm. The LHWs will each recruit 12 participants from their social network for a total of 312 participants in each arm. The intervention group participants will be exposed to 2 LHWO sessions and 2 telephone calls aimed at increasing their CRC screening receipt. The comparison group will receive a bilingual CRC brochure as well as a lecture on healthy nutrition for cardiovascular health. Effectiveness of the intervention will be measured by pre-intervention and post-intervention surveys of community participants' CRC screening behaviors, with validation of self-reports. The second aim is to examine the processes through which LHWs work as health educators in this community. This aim will be achieved by using mixed methods including surveys (of the LHWs and participants), focus groups (of the LHWs and participants), and observations conducted during LHW educational sessions. The third aim is to examine and expand the current paradigm of lay health education in Asian communities by exploring the roles that TCM practitioners such as herbalists and acupuncturists may play in delivering health education messages focused on a biomedical model of cancer prevention. This aim will be implemented and evaluated using the methodologies employed in the developmental, implementation, and evaluation process in the prior 2 aims. The proposal also will explore ways through which LHWO can be disseminated and community capacity can be sustained. The findings of this project will greatly expand understanding about effective and culturally appropriate cancer health promotion among ethnic minority communities.